static_lambda → hill_occupancy → adaptive_receptor  ·  The loop climbs the ladder emergently from the graded tests: static_lambda fails receptor_gating (0.69, ignores the block — not receptor-mediated); hill_occupancy fails recruits_high (0.00 — fixed-kd occupancy saturates on both sides of the gradient at high background); adaptive_receptor re-centers its kd on the local mean (fold-change detection) and clears all three. Bands: recruits_low [0.4,1.0], recruits_high [0.35,1.0], receptor_gating ≤0.15.